ThreatLocker Audit Log

What the API calls the "audit" endpoints, the ThreatLocker UI calls the Action Log — the same data either way. Every execution attempt, every block, every permit, every audit-only match generates an entry. This is your forensics surface: when something happened on an endpoint, this is where you find out what.

API Tools

Search Action Log

threatlocker_audit_search

POST-based GetByParameters. Common filters via the body:

• searchText — substring across file name, path, computer name, user
• Date-range fields (typically fromDate / toDate in ISO 8601 UTC)
• pageNumber, pageSize, orderBy: "actionTime", isAscending: false (newest first is the usual default)
• organizationId header for tenant scoping

Each row typically includes actionId, actionTime, kindOfAction (Block, Permit, Audit), fileName, filePath, fileHash, signer, computerName, userName, policyName, and processChain (parent process info).

Get Action Detail

threatlocker_audit_get

Returns a single action with full context — full process tree, command line, network endpoints contacted (when available), and any related actions clustered around the same event.

File History

threatlocker_audit_file_history

Aggregates all Action Log entries for a given file path or hash. Use this when you have a candidate IOC and want to know everywhere it appeared in the fleet, when, and what happened each time.

kindOfAction Categorization

Block + Audit together is the high-signal pair for hunting:

• A Block event is your control working as designed.
• An Audit event in Secured Mode means something matched a watch rule but was not stopped — investigate.
• An Audit event in Learning Mode is just baseline data, less actionable.

Common Workflows

Timeline Around a Security Event

When given "something happened on host X around time T":

1. threatlocker_audit_search with searchText: "<host>", fromDate: T - 1h, toDate: T + 1h, orderBy: "actionTime", isAscending: true.
2. Read forward through the timeline and look for the inflection — the first unusual binary, the first child process from a known LOLBin parent, the first network-active process.
3. For any anomaly, call threatlocker_audit_get for the full detail and add the parent process to your investigation list.
4. Pivot on fileHash of the suspicious binary using threatlocker_audit_file_history to see where else in the fleet it appeared.

File-Path-Across-Endpoints Investigation

When given an IOC (path or hash):

1. threatlocker_audit_file_history with the IOC.
2. Bucket results by computerName — which endpoints saw it?
3. For each affected endpoint, note the earliest actionTime — the spread pattern often points to patient zero.
4. For every Permit action against the IOC, that endpoint may have been impacted. For every Block, you have evidence the control stopped it.

Repeated Denials From the Same Source

A pattern worth surfacing: same user or same computer generating many Block events in a short window.

1. Search a recent window with kindOfAction: "Block".
2. Group results client-side by userName and computerName.
3. Anyone with > N blocks in a short window is either:
   • A user fighting their tooling (open an approval — see approval-requests skill).
   • A compromised account or malware retrying execution.

Policy Bypass / Audit-Only Match Correlation

1. Search with kindOfAction: "Audit".
2. Filter to Secured-Mode endpoints (cross-reference computers via threatlocker_computers_get — policyMode).
3. Each Audit hit on a Secured endpoint indicates a watch rule fired without enforcement — review the rule and decide if it should become a Block.

Date-Range Filter Patterns

• Last hour — now - 1h to now. Tight, high-signal.
• Last 24h — Daily triage and report scope.
• Last 7d — Threat-hunting baseline.
• Around an alert — alertTime ± 30m is usually enough; expand if the parent process is unclear.

Always send dates in ISO 8601 UTC. The Action Log itself stores UTC.

Edge Cases

• High-volume endpoints — Build servers, dev workstations and jump boxes can generate thousands of audit rows per day. Use tight date windows or signer filters to keep result sets manageable.
• Duplicate-looking events — A single execution can produce multiple log rows (file open, hash check, network connect). Always read the actionId to confirm uniqueness.
• Truncated process chains — processChain is best-effort. If the parent is empty or unknown, treat the row as a starting point for further investigation, not a final answer.

Best Practices

• Start with the tightest possible time window; expand only if needed.
• Always pivot on fileHash rather than filePath for IOC work — attackers rename binaries, hashes don't change.
• Capture actionId references in any incident write-up so a reviewer can re-pull the exact source rows.
• Cross-reference findings with approval-requests — a recent approval may explain an otherwise suspicious Permit.

Related Skills

• api-patterns — Auth and pagination
• computers — Endpoint policy mode context
• approval-requests — Decisions that produce Permit actions
• organizations — Multi-tenant pivot